As part of a Department of Energy’s Oak Ridge National Laboratory research project to verify the transformative possibilities of 3D printing for concrete applications, GATE Precast used 3D printed concrete formwork in the fabrication of One South First, a towering mixed-used structure with a unique façade in Brooklyn’s Williamsburg neighborhood.
Through a design-assist relationship, GATE, Two Trees and world-renowned architects COOKFOX refined some of the window profiles on the tower to make it cost-effective and practical to use 3D printed forms. The multi-faceted window panels include aluminum framing and glass pre-assembled and caulked at GATE's fabrication facilities prior to shipping to the jobsite, streamlining the installation of the façade.
Pre-installed windows conservatively saved eight months on the schedule of the Residential Tower (42 stories) and the Ten Grand Street Office Tower (22 stories) and allowed the interiors program to start earlier than the traditional delivery methods of windows.
The façade design is inspired by sugar’s crystalline structure, which connects the building with the industrial history of the Domino Sugar site. GATE utilized a super white, sand-rich mix to mimic the size, shape and color of sugar crystals. Casting on the 3D printed forms provided the added benefit of incredibly sharp details and improved finishes. The window openings were deep-set and the sides were faceted back at different angles to catch the light and show the sparkle of the glitter sand used in the acid-etched white concrete. The front faces of the panels were polished to give a smooth reflective surface to complement the acid-washed angled surfaces. The layout of the molds in the panel were varied throughout the building to give an appearance of randomness.
These molds proved more durable than traditional wood molds, allowing for greater use and minimal waste.